Embodiments of the present disclosure generally relate to respiration. More specifically, the present disclosure relates to apparatus and methods for stimulating respiration during sleep.
A clinical pathologic entity called Sleep Apnea Syndrome (SAS) affects many individuals around the world. SAS is currently generally characterized by repetitive stops of respiration. SAS may cause severe disturbances of sleep, and may have deleterious effects on mental activities, such as intellectual performance, memory, and behavior. Further, SAS is known as one of the causes of cardiovascular diseases, increased blood pressure (hypertension), stroke, heart arrhythmia, and conduction disturbances, which may lead to fatal cardiac arrest. SAS is especially dangerous in patents having chronic lung and heart diseases.
A common means of physiologic protection against SAS is usually arousal from sleep and the restoration of normal breathing as a result of temporary normalization of the cortical neural control of respiration. However, as expected, these repetitive arousals result in fragmented and disturbed sleep.
Current treatments of SAS have been limited to mechanical stenting of the airway via CPAP (continuous positive airway pressure) devices and oral appliances, as well as surgical procedures aimed at removing, reducing, repositioning, or stiffening tissue in the upper airway. CPAP and oral devices currently have only a 50%-60% compliance rate because of patients' feelings of claustrophobia, nasal stuffiness, and inconvenience related to these devices' awkward and cumbersome equipment. Moreover, surgical treatments are usually very painful, require the use of general anesthesia, and can have severe complications. In the medical literature, surgical interventions are, at best, about 60-70% effective at curing SAS.